Break out the party hats. Astronomers have all but confirmed that the second known interstellar object is currently whizzing through our Solar System – and unlike the first event, we’ll be able to study it in a huge amount of detail.
The object was originally given the moniker gb00234, and was discovered by an amateur astronomer called Gennady Borisov in Crimea using his own observatory called MARGO. Borisov first spotted the object on August 30 and was immediately alerted by its odd path – suggesting it was not bound to our Sun.
Subsequent analysis and observations have confirmed the object has a high eccentricity, meaning it is on a hyperbolic path that will take it in and out of our Solar System, never to return. The Minor Planet Center (MPC) at the Harvard-Smithsonian Center for Astrophysics confirmed the orbit of the object earlier today and gave it a new name in honor of its discoverer: C/2019 Q4 (Borisov).
“We were somewhat cautious as to whether it was hyperbolic or not,” says Matthew Payne from the MPC. “Over the course of the past few days, it became increasingly apparent that it looks like it has a hyperbolic trajectory.”
As mentioned this would be the second known interstellar object to enter our Solar System, since a first called ‘Oumuamua (or 1I/2017 U1) was spotted in October 2017. Both are believed to have traveled from other planetary systems to our own across the vast expanse of the galaxy over millions or even billions of years.
There are a couple of key differences this time around though. The first is that from images, we are fairly certain C/2019 (which will likely be given the label 2I/2019) is a comet about 10 kilometers across as it appears to have a visible tail, whereas ‘Oumuamua appeared to be something more sedate.